I trying to build a dynamic query similar to:
def domain = DomainName
def ids = 1
def domainClass = "$domain" as Class
domainClass.find("from ${domain} as m where m.job = ${ids} ").id
But it's not working.
If I'm trying this, all is fine:
def domain = DomainName
def ids = 1
DomainName.find("from ${domain} as m where m.job = ${ids} ").id
How can I use dynamic domain class name with find?
The simplest way is to use the getDomainClass method:
String domainClassName = 'com.foo.bar.Person'
def ids = 1
def domainClass = grailsApplication.getDomainClass(domainClassName).clazz
domainClass.find("from $domainClassName as m where m.job = ${ids} ").id
Note that if you're trying to get a single instance by id, use get:
long id = 1234
def person = domainClass.get(id)
and if you want to get multiple instances and you have a list of ids, you can use getAll
def ids = [1,2,3,4,5]
def people = domainClass.getAll(ids)
Also it's a REALLY bad idea to use GStrings with property values embedded - Google 'SQL Injection'
For example to find a person by username:
String username = 'foo'
def person = domainClass.find(
"from $domainClassName as m where m.username=:username",
[username: username])
You should be able to do this by explicitly using the GroovyClassLoader:
def domain = "DomainName"
def c = new GroovyClassLoader().loadClass(domain)
c.find('...').id
The best way to get a Domain class dynamically is through the GrailsApplication object. Example:
import org.codehaus.groovy.grails.commons.ApplicationHolder
def domainName = "full.package.DomainName"
def domainGrailsClass = ApplicationHolder.application.getArtefact("Domain", domainName)
def domainClass = domainGrailsClass.getClazz()
domainClass.find("from ${domainGrailsClass.name} as m where m.job = ${ids}").id
You can also use Class.forName() just as you would in Java. Use the 3 parameter version and pass in the current thread context class loader:
import grails.util.GrailsNameUtils
def domainName = "full.package.DomainName"
def domainClass = Class.forName(domainName, true, Thread.currentThread().getContextClassLoader())
domainClass.find("from ${GrailsNameUtils.getShortName(domainName)} as m where m.job = ${ids}").id
Classloaders are an ugly topic in Java and JVM frameworks. In Grails, you almost always want to use the thread context classloader. But even better is to use the GrailsApplication interface and avoid the issue altogether.
use GrailsClassUtils
GrailsClassUtils.getShortName(DomainName)
to get the name of the class, so this should work... if I understood the question
def domainClassName = GrailsClassUtils.getShortName(DomainName)
def ids = 1
DomainName.find("from ${domainClassName} as m where m.job = ${ids} ").id
Related
So I have a join model defined as follow:
class EventTrack(models.Model):
dj = models.ForeignKey(DjProfile, blank=True)
track = models.ForeignKey(Track, blank=True)
event = models.ForeignKey(Event, blank=True)
def __str__(self):
return '%s - %s' % (self.event, self.track)
Is there a way I can use django-autocomplete-light with this model?
I know how to use it with inline models, but I don't get how to use it with standard field (in this case they are fk though).
At the moment I have the follow, which does not include the autocomplete functionality:
class EventTrackAdmin(admin.ModelAdmin):
fields = ['event', 'dj', 'track']
list_display = ('event', 'dj', 'track')
search_fields = ['event', 'dj', 'track']
admin.site.register(EventTrack, EventTrackAdmin)
edit:
I defined a DjForm as follow:
class DjForm(ModelForm):
dj = ModelChoiceField(
queryset=DjProfile.objects.all(),
widget=autocomplete.ModelSelect2(url='dj-autocomplete')
)
class Meta:
model = DjProfile
fields = '__all__'
Views:
#method_decorator(login_required, name='dispatch')
class DjProfileAutocomplete(autocomplete.Select2QuerySetView):
def get_queryset(self):
# Don't forget to filter out results depending on the visitor !
if not self.request.user.is_authenticated():
return DjProfile.objects.none()
qs = DjProfile.objects.all()
if self.q:
qs = qs.filter(name__istartswith=self.q)
return qs
And routing:
from frontend.views import DjProfileAutocomplete
urlpatterns = [
url(r'^admin/', admin.site.urls),
url(r'^dj-autocomplete/$', DjProfileAutocomplete.as_view(create_field='name'), name='dj-autocomplete'),
]
Everything works fine, and if I browse the endpoint I get the json with Djs result. My only problem is to use this in the EventTrack Model, in the admin.
sooo, actually it was easy:
forms.py
class EventTrackForm(ModelForm):
dj = ModelChoiceField(
queryset=DjProfile.objects.all(),
widget=autocomplete.ModelSelect2(url='dj-autocomplete')
)
class Meta:
model = EventTrack
fields = '__all__'
admin.py
class EventTrackAdmin(admin.ModelAdmin):
form = EventTrackForm
...
I'm trying to get the list of a specific rental from the current user.
Code in controller:
def index() {
if (isLoggedIn()) {
String username = getPrincipal().username
def accountInstance = Account.findByUsername(username)
def rentalInstanceList = Rental.findAll("from Rental as r where r.account_id=:accountid", [accountid: accountInstance.id])
}
}
account_id is a foreign key.
After running I get the error:
could not resolve property: account_id of: ers.Rental
What am I doing wrong?
Generally, in HQL you have to use the field names as defined in your domain classes. So, your query should look like:
def list = Rental.findAll("from Rental where accountId=:accountid", [accountid: accountInstance.id])
or
def list = Rental.findAllByAccount accountInstance
or even
def list = Rental.findAllByAccount getPrincipal()
if the return type of getPrincipal() has the id field.
findAll is not limited to instances of the calling class so I use executeQuery instead. https://stackoverflow.com/a/8916483/5011228
I have a method:
def nameToCode(nameStr){
def ret = resortService.getResort("all")
//this gets like 180 objects with various properties like name, code, etc.
def resorts = [name: ret.prName, code: ret.prProductIndex]
def code = resorts.findByName(nameStr) //this doesn't work
println(code)
return code
}
I'm trying to call this method and send it a name. It's then supposed to go find the name in the map, if it finds it it's supposed to return the name's code. This is supposed to be simple but I've been searching everywhere and can't figure out how to do this. I'll appreciate any help. Thanks
you are using a gorm method on a standard map:
Instead of :
def resorts = [name: ret.prName, code: ret.prProductIndex]
def code = resorts.findByName(nameStr) //this doesn't work
Try:
def resorts = [name: ret.prName, code: ret.prProductIndex]
def code = resorts.findAll{name==nameStr}
Is their a dynamic namedquery on grails? Im not sure if its the right term but, I mean a namedquery that can be true to all.
Something like:
namedQueries = {
dynamicQuery{ term, name, value ->
term(name, value)
}
}
Then it can be called maybe like but not exactly:
def testClass = TestClass.dynamicQuery('eq', 'lastname', 'Bill').list()
and so you call it too like:
def testClass = TestClass.dynamicQuery('gt', 'id', 12).list()
This one might not work but is their something similar in grails?
UPDATE
The idea is that so I can chained it as many as I want like:
def testClass = TestClass.dynamicQuery('gt', 'id', 12).dynamicQuery('eq', 'stat', 11).list()
This is so that I dont have to create many namedqueries. I was hoping I can create one and use it multiple times.
Grails' createCriteria method generates Grails HibernateCriteriaBuilder instance, within which you can call invokeMethod method to dynamically create query criteria, which usually is defined by the standard DSL.
Here is a example in some controller:
private String dynamicCriteriaTest(String term, name, value) {
def c = TestClass.createCriteria()
def param = []
param << name
param << value
def result = c.list{
c.invokeMethod(term, param as Object[])
}
return result.toString()
}
def test() {
render dynamicCriteriaTest('eq','lastname','Bill')
}
That will get something you want.
update
If you want to call this method multiple times, pass the criteria parameters in an a List then execute the query:
private List dynamicCriteriaTest(List param) {
def c = TestClass.createCriteria()
def paramList = param.collate(3) //split the parameters into groups
def result = c.list{
paramList.each { paramInstance ->
def command = paramInstance[0]
paramInstance.remove(0)
c.invokeMethod(command, paramInstance as Object[])
}
}
return result
}
def test() {
ArrayList param = new ArrayList()
//the 1st criteria
param << 'gt'
param << 'id'
param << (long)12 //you have to check the Grails [HibernateCriteriaBuilder] API to make sure the parameter passed to `invokeMethod` is in the right type (e.g. **long** in this case)
//the 2nd one
param << 'eq'
param << 'stat'
param << (long)11
//even more
param << 'like'
param << 'description'
param << 'some text%'
render dynamicCriteriaTest(param)
}
In Grails you have NamedQueries and also Where Queries. The example you give can possibly be implemented by using a namedqueries and placing this in a abstract domain class. Your domain classes should extend this abstract domain.
I have the following models:
class Message(models.Model):
date = models.DateTimeField()
user = models.ForeignKey(User)
thread = models.ForeignKey('self', blank=True, null=True)
...
class Forum(models.Model):
name = models.CharField(max_length=24)
messages = models.ManyToManyField(Message, through="Message_forum", blank=True, null=True)
...
class Message_forum(models.Model):
message = models.ForeignKey(Message)
forum = models.ForeignKey(Forum)
status = models.IntegerField()
position = models.IntegerField(blank=True, null=True)
tags = models.ManyToManyField(Tag, blank=True, null=True)
In the admin site, when I go to add/change a forum, I don't see the messages listbox as you'd expect. However, it shows up if I remove the 'through' parameter in the ManyToManyField declaration. What's up with that? I've registered all three models (plus Tag) to the admin site in admin.py.
TIA
Documentation says:
When you specify an intermediary model using the through argument to a
ManyToManyField, the admin will not display a widget by default.
But it's probably possible to display M2M fields in the admin change view even if the through attribute is defined.
class ForumAdminForm(forms.ModelForm):
mm = forms.ModelMultipleChoiceField(
queryset=models.Message.objects.all(),
widget=FilteredSelectMultiple(_('ss'), False, attrs={'rows':'10'}))
def __init__(self, *args, **kwargs):
if 'instance' in kwargs:
initial = kwargs.setdefault('initial', {})
initial['mm'] = [t.service.pk for t in kwargs['instance'].message_forum_set.all()]
forms.ModelForm.__init__(self, *args, **kwargs)
def save(self, commit=True):
instance = forms.ModelForm.save(self, commit)
old_save_m2m = self.save_m2m
def save_m2m():
old_save_m2m()
messages = [s for s in self.cleaned_data['ss']]
for mf in instance.message_forum_set.all():
if mf.service not in messages:
mf.delete()
else:
messages.remove(mf.service)
for message in messages:
Message_forum.objects.create(message=message, forum=instance)
self.save_m2m = save_m2m
return instance
class Meta:
model = models.Forum
class ForumAdmin(admin.ModelAdmin):
form = ForumAdminForm
Take a look at the official documentation:
I learned a lot from #Fedor's answer, but some comments and cleanup may be still beneficial.
class ForumAdminForm(forms.ModelForm):
messages = forms.ModelMultipleChoiceField(
queryset=Message.objects.all(),
widget=FilteredSelectMultiple('Message', False))
# Technically, you don't need to manually set initial here for ForumAdminForm
# However, you NEED to do the following for MessageAdminForm
def __init__(self, *args, **kwargs):
if 'instance' in kwargs:
# a record is being changed. building initial
initial = kwargs.setdefault('initial', {})
initial['messages'] = [t.message.pk for t in kwargs['instance'].message_forum_set.all()]
super(ForumAdminForm, self).__init__(*args, **kwargs)
def save(self, commit=True):
if not self.is_valid():
raise HttpResponseForbidden
instance = super(ForumAdminForm, self).save(self, commit)
def save_m2m_with_through():
messages = [t for t in self.cleaned_data['messages']
old_memberships = instance.message_forum_set.all()
for old in old_memberships:
if old.message not in messages:
# and old membership is cleaned by the user
old.delete()
for message in [x for x in messages not in map(lambda x: x.message, old_memberships)]:
membership = Member_forum(message=messsage, forum=instance)
# You may have to initialize status, position and tag for your need
membership.save()
if commit:
save_m2m_with_through()
else:
self.save_m2m = save_m2m_with_through
return instance
class Meta:
model = Forum
fields = {'name', 'messages')
There's one caveat: if you have another many-to-many relationship in the models (that is without through), super(ForumAdminForm, self).save(self, commit) will set self.save_m2m in case commit is False. However, calling this would cause an error, because this function also tries to save the many-to-many with through as well. You may need to save all other many-to-many relationship manually, or catch the exception, or else.
Django admin nicely support many-to-many intermediary models that using the through argument .
For example you have these Person and Group models with intermediate Membership model:
models.py
from django.db import models
class Person(models.Model):
name = models.CharField(max_length=128)
class Group(models.Model):
name = models.CharField(max_length=128)
members = models.ManyToManyField(Person, through='Membership')
class Membership(models.Model):
person = models.ForeignKey(Person, on_delete=models.CASCADE)
group = models.ForeignKey(Group, on_delete=models.CASCADE)
date_joined = models.DateField()
invite_reason = models.CharField(max_length=64)
Now in admin.py file ,
Define an inline class for the intermediate Membership model:
#admin.register(Membership)
class MembershipInline(admin.TabularInline):
model = Membership
extra = 1
And use them in admin views of models:
#admin.register(Person)
class PersonAdmin(admin.ModelAdmin):
inlines = (MembershipInline,)
#admin.register(Group)
class GroupAdmin(admin.ModelAdmin):
inlines = (MembershipInline,)
More info in official docs:
Models,
Admin